chore: Update discovery artifacts (#1336)

## Deleted keys were detected in the following stable discovery artifacts:
servicemanagementv1[ [More details]](https://github.com/googleapis/google-api-python-client/commit/6e593517543990b40c8c6a4c2512e176a0b896f4)

## Discovery Artifact Change Summary:
contentv21[ [More details]](https://github.com/googleapis/google-api-python-client/commit/e18a707b3351372b6bad9961a3cc0a1087fb907b)
dnsv1beta2[ [More details]](https://github.com/googleapis/google-api-python-client/commit/bb15dc54f5f110036bdb96d247d20f6908324547)
servicemanagementv1[ [More details]](https://github.com/googleapis/google-api-python-client/commit/6e593517543990b40c8c6a4c2512e176a0b896f4)
translatev3beta1[ [More details]](https://github.com/googleapis/google-api-python-client/commit/0ab9156b06cbc33b173851b20ab73bdd06522fe8)

chore(acceleratedmobilepageurl): update the api
chore(accessapproval): update the api
chore(adexchangebuyer): update the api
chore(adexchangebuyer2): update the api
chore(admob): update the api
chore(analyticsadmin): update the api
chore(analyticsdata): update the api
chore(analyticsreporting): update the api
chore(androiddeviceprovisioning): update the api
chore(androidmanagement): update the api
chore(apigateway): update the api
chore(apikeys): update the api
chore(area120tables): update the api
chore(calendar): update the api
chore(chromemanagement): update the api
chore(chromepolicy): update the api
chore(cloudchannel): update the api
chore(cloudkms): update the api
chore(cloudtasks): update the api
chore(composer): update the api
feat(content): update the api
chore(customsearch): update the api
chore(datastore): update the api
chore(dialogflow): update the api
chore(digitalassetlinks): update the api
feat(dns): update the api
chore(docs): update the api
chore(domainsrdap): update the api
chore(essentialcontacts): update the api
chore(eventarc): update the api
chore(factchecktools): update the api
chore(file): update the api
chore(firebase): update the api
chore(firebasedatabase): update the api
chore(firestore): update the api
chore(gmailpostmastertools): update the api
chore(indexing): update the api
chore(jobs): update the api
chore(libraryagent): update the api
chore(licensing): update the api
chore(manufacturers): update the api
chore(mybusinessaccountmanagement): update the api
chore(mybusinesslodging): update the api
chore(mybusinessplaceactions): update the api
chore(orgpolicy): update the api
chore(pagespeedonline): update the api
chore(paymentsresellersubscription): update the api
chore(policytroubleshooter): update the api
chore(prod_tt_sasportal): update the api
chore(realtimebidding): update the api
chore(runtimeconfig): update the api
chore(safebrowsing): update the api
chore(script): update the api
chore(serviceconsumermanagement): update the api
feat(servicemanagement): update the api
chore(serviceusage): update the api
chore(slides): update the api
chore(storage): update the api
chore(streetviewpublish): update the api
chore(tasks): update the api
chore(toolresults): update the api
feat(translate): update the api
chore(workflows): update the api
chore(youtube): update the api
chore(youtubeAnalytics): update the api
chore(youtubereporting): update the api
chore(docs): Add new discovery artifacts and reference documents
diff --git a/docs/dyn/dialogflow_v3beta1.projects.locations.agents.environments.sessions.html b/docs/dyn/dialogflow_v3beta1.projects.locations.agents.environments.sessions.html
index a0bf6bd..ff9f3c7 100644
--- a/docs/dyn/dialogflow_v3beta1.projects.locations.agents.environments.sessions.html
+++ b/docs/dyn/dialogflow_v3beta1.projects.locations.agents.environments.sessions.html
@@ -164,7 +164,7 @@
     "parameters": { # Additional parameters to be put into session parameters. To remove a parameter from the session, clients should explicitly set the parameter value to null. Depending on your protocol or client library language, this is a map, associative array, symbol table, dictionary, or JSON object composed of a collection of (MapKey, MapValue) pairs: - MapKey type: string - MapKey value: parameter name - MapValue type: - If parameter's entity type is a composite entity: map - Else: depending on parameter value type, could be one of string, number, boolean, null, list or map - MapValue value: - If parameter's entity type is a composite entity: map from composite entity property names to property values - Else: parameter value
       "a_key": "", # Properties of the object.
     },
-    "payload": { # This field can be used to pass custom data into the webhook associated with the agent. Arbitrary JSON objects are supported. Some integrations that query a Dialogflow agent may provide additional information in the payload. In particular, for the Dialogflow Phone Gateway integration, this field has the form: { "telephony": { "caller_id": "+18558363987" } }
+    "payload": { # This field can be used to pass custom data into the webhook associated with the agent. Arbitrary JSON objects are supported. Some integrations that query a Dialogflow agent may provide additional information in the payload. In particular, for the Dialogflow Phone Gateway integration, this field has the form: ``` { "telephony": { "caller_id": "+18558363987" } } ```
       "a_key": "", # Properties of the object.
     },
     "sessionEntityTypes": [ # Additional session entity types to replace or extend developer entity types with. The entity synonyms apply to all languages and persist for the session of this query.
@@ -1041,7 +1041,7 @@
       "parameters": { # Additional parameters to be put into session parameters. To remove a parameter from the session, clients should explicitly set the parameter value to null. Depending on your protocol or client library language, this is a map, associative array, symbol table, dictionary, or JSON object composed of a collection of (MapKey, MapValue) pairs: - MapKey type: string - MapKey value: parameter name - MapValue type: - If parameter's entity type is a composite entity: map - Else: depending on parameter value type, could be one of string, number, boolean, null, list or map - MapValue value: - If parameter's entity type is a composite entity: map from composite entity property names to property values - Else: parameter value
         "a_key": "", # Properties of the object.
       },
-      "payload": { # This field can be used to pass custom data into the webhook associated with the agent. Arbitrary JSON objects are supported. Some integrations that query a Dialogflow agent may provide additional information in the payload. In particular, for the Dialogflow Phone Gateway integration, this field has the form: { "telephony": { "caller_id": "+18558363987" } }
+      "payload": { # This field can be used to pass custom data into the webhook associated with the agent. Arbitrary JSON objects are supported. Some integrations that query a Dialogflow agent may provide additional information in the payload. In particular, for the Dialogflow Phone Gateway integration, this field has the form: ``` { "telephony": { "caller_id": "+18558363987" } } ```
         "a_key": "", # Properties of the object.
       },
       "sessionEntityTypes": [ # Additional session entity types to replace or extend developer entity types with. The entity synonyms apply to all languages and persist for the session of this query.
@@ -1895,7 +1895,7 @@
     "parameters": { # Additional parameters to be put into session parameters. To remove a parameter from the session, clients should explicitly set the parameter value to null. Depending on your protocol or client library language, this is a map, associative array, symbol table, dictionary, or JSON object composed of a collection of (MapKey, MapValue) pairs: - MapKey type: string - MapKey value: parameter name - MapValue type: - If parameter's entity type is a composite entity: map - Else: depending on parameter value type, could be one of string, number, boolean, null, list or map - MapValue value: - If parameter's entity type is a composite entity: map from composite entity property names to property values - Else: parameter value
       "a_key": "", # Properties of the object.
     },
-    "payload": { # This field can be used to pass custom data into the webhook associated with the agent. Arbitrary JSON objects are supported. Some integrations that query a Dialogflow agent may provide additional information in the payload. In particular, for the Dialogflow Phone Gateway integration, this field has the form: { "telephony": { "caller_id": "+18558363987" } }
+    "payload": { # This field can be used to pass custom data into the webhook associated with the agent. Arbitrary JSON objects are supported. Some integrations that query a Dialogflow agent may provide additional information in the payload. In particular, for the Dialogflow Phone Gateway integration, this field has the form: ``` { "telephony": { "caller_id": "+18558363987" } } ```
       "a_key": "", # Properties of the object.
     },
     "sessionEntityTypes": [ # Additional session entity types to replace or extend developer entity types with. The entity synonyms apply to all languages and persist for the session of this query.